Improvement in stove-pipe dampers



UNITED STATES PATENT OEEIcE.

BRIDGET FRENCH, OF ROCHESTER, NEW YORK.

IMPROVEMENT IN STOVE-PIPE DAMPERS.

Specification forming part of Letters Patent No. 117,762, dated August8, 1871.

To all whom it may concern:

Be it known that I, BRIDGET FRENCH, of the city of Rochester, in thecounty of Monroe and State of New York, have invented a certain new anduseful Improvement in Dampers for Stove- Pipes, of which the followingis a specification:

The object of my invention is to facilitate the escape of gas; andconsists in constructing the damper with conical nipples on one side.

In the drawing, Figure l is a perspective view of my improved damper;Fig. 2, a section through one of the conical nipples 5 Fig. 3, a view ofthe axis of the damper.

A represents the damper-plate, which is of the usual circular form tolit in the pipe. On one side it has a series of conical nipples c a.,which is distributed over the whole surface. These nipples are madehollow, and at the apex or top are small perforations b b, whichestablish constant communication between the spaces above and below thedamper.

The special object of these conical nipples is to facilitate the escapeof gas without at the same time allowing a free draught, which occurswhen the damper is partiallyT or wholly open. When the apexes are turnedupward, as in Fig. 1, the tendency is to concentrate in the cones theproducts passing upward and allow them to escape more readily by suchconcentration, especially as a kind of auxiliary draught is produced bythe cones, which act to a certain' degree as chimneys when the currentsthrough the pipe are varied by wind or otherwise.

When turned down, as shown by the dotted lines in Fig. 2, the apexesproduce the opposite effect, by diiiusing instead of concentrating; andby projecting a distance below the surface of the damper prevent a rapidescape and deaden the action of the re,but at the same time allow thegas to escape by its tendency to pass upward rapidly. In the first-namedposition the cones prevent gusts of wind from affecting the fire, bydiifusing the currents. They also equalize the draught from below, andprevent any countercurrents that might arise by concentrating on oneside more than the other. The disk of the damper is provided with lugs,through which passes the axis B. This axis has a handle, d, and twodisks or enlargements, f f7, with a space, g, between, at 011e end, andat the other it has a loose'ball, h, held in place -by a pin, k, whichits in any of a series of holes, m m, of the axis.

When the damper islocated between two joints of pipe one edge of thepipe rests between the disks f j", which keep the axis rmly in place andprevent any end movement. When located intermediately in a singlelength, however, the axis is run through, and the side of the pipe restsinside the inner disk ff. The opposite end of the axis is passed throughthe opposite side of the pipe, and the ball It is then slipped up on theoutside and held by the pin, as before described.

This arrangement of the axis, with the two disks ff', and with the looseball l1. held by the pin in the adjusting-holes, is new as far as I amaware, and forms one feature of my invention. By this means it isspecially adapted to insertion either at the joints of the pipe orinside the separate lengths. The ball enables the axis to be removed atpleasure, and the adjusting-holes allow it to be placed in large orsmall pipes. This device is applicable both to coal and woodstoves.

I do not claim simple holes formed near the rim of the damper, as I amaware that the same are not new; but

What I claim, and desire to secure by Letters Patent, as a new articleof manufacture, is-

The damper A, provided with the projecting conical nipples a c,distributed over the surface, arranged as described, and operating inthe manner and for the purpose specified.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

BRIDGET FRENCH.

' Witnesses:

R. F. Oscoop, ARCHE. BAINE.

